//
// WorkoutLogListView.swift
// Workouts Watch App
//
// Copyright 2025 Rouslan Zenetl. All Rights Reserved.
//

import SwiftUI
import CoreData

struct WorkoutLogListView: View {
    @Environment(\.managedObjectContext) private var viewContext

    @ObservedObject var workout: Workout

    @State private var showingExercisePicker = false
    @State private var selectedLog: WorkoutLog?

    var sortedWorkoutLogs: [WorkoutLog] {
        workout.logsArray
    }

    var body: some View {
        List {
            Section(header: Text(workout.label)) {
                ForEach(sortedWorkoutLogs, id: \.objectID) { log in
                    Button {
                        selectedLog = log
                    } label: {
                        WorkoutLogRowLabel(log: log)
                    }
                    .buttonStyle(.plain)
                }
            }

            Section {
                Button {
                    showingExercisePicker = true
                } label: {
                    HStack {
                        Image(systemName: "plus.circle.fill")
                            .foregroundColor(.green)
                        Text("Add Exercise")
                    }
                }
            }
        }
        .overlay {
            if sortedWorkoutLogs.isEmpty {
                ContentUnavailableView(
                    "No Exercises",
                    systemImage: "figure.strengthtraining.traditional",
                    description: Text("Tap + to add exercises.")
                )
            }
        }
        .navigationTitle(workout.split?.name ?? Split.unnamed)
        .navigationDestination(item: $selectedLog) { log in
            ExerciseProgressView(workoutLog: log)
        }
        .sheet(isPresented: $showingExercisePicker) {
            ExercisePickerView(workout: workout)
        }
    }

}

// MARK: - Workout Log Row Label

struct WorkoutLogRowLabel: View {
    @ObservedObject var log: WorkoutLog

    var body: some View {
        HStack {
            statusIcon
                .foregroundColor(statusColor)

            VStack(alignment: .leading, spacing: 2) {
                Text(log.exerciseName)
                    .font(.headline)
                    .lineLimit(1)

                Text(subtitle)
                    .font(.caption2)
                    .foregroundColor(.secondary)
            }

            Spacer()
        }
    }

    private var statusIcon: Image {
        switch log.status {
        case .completed:
            Image(systemName: "checkmark.circle.fill")
        case .inProgress:
            Image(systemName: "circle.dotted")
        case .notStarted:
            Image(systemName: "circle")
        case .skipped:
            Image(systemName: "xmark.circle")
        }
    }

    private var statusColor: Color {
        switch log.status {
        case .completed:
            .green
        case .inProgress:
            .orange
        case .notStarted:
            .secondary
        case .skipped:
            .secondary
        }
    }

    private var subtitle: String {
        if log.loadTypeEnum == .duration {
            let mins = log.durationMinutes
            let secs = log.durationSeconds
            if mins > 0 && secs > 0 {
                return "\(log.sets) × \(mins)m \(secs)s"
            } else if mins > 0 {
                return "\(log.sets) × \(mins) min"
            } else {
                return "\(log.sets) × \(secs) sec"
            }
        } else {
            return "\(log.sets) × \(log.reps) × \(log.weight) lbs"
        }
    }
}

// MARK: - Exercise Picker View

struct ExercisePickerView: View {
    @Environment(\.managedObjectContext) private var viewContext
    @Environment(\.dismiss) private var dismiss

    @ObservedObject var workout: Workout

    private var availableExercises: [Exercise] {
        guard let split = workout.split else { return [] }
        let existingNames = Set(workout.logsArray.map { $0.exerciseName })
        return split.exercisesArray.filter { !existingNames.contains($0.name) }
    }

    var body: some View {
        NavigationStack {
            List {
                if availableExercises.isEmpty {
                    Text("All exercises added")
                        .foregroundColor(.secondary)
                } else {
                    ForEach(availableExercises, id: \.objectID) { exercise in
                        Button {
                            addExercise(exercise)
                        } label: {
                            VStack(alignment: .leading) {
                                Text(exercise.name)
                                    .font(.headline)
                                Text(exerciseSubtitle(exercise))
                                    .font(.caption2)
                                    .foregroundColor(.secondary)
                            }
                        }
                    }
                }
            }
            .navigationTitle("Add Exercise")
            .toolbar {
                ToolbarItem(placement: .cancellationAction) {
                    Button("Cancel") {
                        dismiss()
                    }
                }
            }
        }
    }

    private func addExercise(_ exercise: Exercise) {
        let log = WorkoutLog(context: viewContext)
        log.exerciseName = exercise.name
        log.date = Date()
        log.order = Int32(workout.logsArray.count)
        log.sets = exercise.sets
        log.reps = exercise.reps
        log.weight = exercise.weight
        log.loadType = exercise.loadType
        log.duration = exercise.duration
        log.status = .notStarted
        log.workout = workout

        // Update workout start if first exercise
        if workout.logsArray.count == 1 {
            workout.start = Date()
        }

        try? viewContext.save()

        // Sync to iOS
        WatchConnectivityManager.shared.syncToiOS()

        dismiss()
    }

    private func exerciseSubtitle(_ exercise: Exercise) -> String {
        let loadType = LoadType(rawValue: Int(exercise.loadType)) ?? .weight
        if loadType == .duration {
            let mins = exercise.durationMinutes
            let secs = exercise.durationSeconds
            if mins > 0 && secs > 0 {
                return "\(exercise.sets) × \(mins)m \(secs)s"
            } else if mins > 0 {
                return "\(exercise.sets) × \(mins) min"
            } else {
                return "\(exercise.sets) × \(secs) sec"
            }
        } else {
            return "\(exercise.sets) × \(exercise.reps) × \(exercise.weight) lbs"
        }
    }
}

#Preview {
    WorkoutLogListView(workout: Workout())
        .environment(\.managedObjectContext, PersistenceController.preview.viewContext)
}